Numerous industries find it desirable to ascertain contents of containers, or to identify materials and fluids. Domestic and international applications exist in, for example, law enforcement, border control, transportation, and shipping. Internationally, ensuring treaty compliance, border control, training, and deterring illicit drug smuggling are significant applications. Other applications include efforts to collect taxes and tariffs, to effectively maintain inventories, and to monitor process flows. Further, material quality and process control are central to achieving high standards of product performance and safety in such industries as food processing and chemical inventory management. Government agencies and homeland security organizations also need ways to cope with increasing investigations involving hazardous chemical, and biological materials, including warfare agents. Due to the large number of containers being shipped both domestically and internationally, there is a need for fast and effective ways for conducting non-intrusive inspection of containers. Such inspections need to quickly identify materials and fluids within the containers and also ascertain presence of objects not expected to be in a container, including, e.g., smuggled contraband. Current systems rely heavily on expensive and time-consuming direct sampling as well as laboratory analyses.
Accordingly, there remains a need for methods and devices providing rapid and reliable inspection data for decision-making purposes for a wide diversity of materials and fluids.